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Finding the Fourth Proportional to 654.80, 981.31 and 361.87

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Solution

The fourth proportional to 654.80, 981.31 and 361.87 is: 542.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.80 : 981.31 = 361.87 : x
  2. Step 2: Convert to fraction form
    654.80/981.31 = 361.87/x
  3. Step 3: Cross multiply
    654.80x = 981.31 × 361.87
  4. Step 4: Simplify right side
    654.80x = 355,102.95
  5. Step 5: Solve for x
    x = 355,102.95/654.80
  6. Step 6: Final answer
    x = 542.31

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.